1. Field of Invention
The present invention relates to an injection apparatus and an injecting process thereof, and more particularly, to a micro-droplet injection apparatus for coating a micro-element and the injecting process thereof.
2. Related Art
Drop-on-Demand Ink Jet Printing technology is a precise coating method with a high reproduction, which uses an injection head to perform micro-droplet injection on injection targets. It can be applied in the formation of conductive traces of various printed circuit board and circuit substrate. Usually, the injection head is moved back and forth in an X-axis direction, and the injection target is moved in a Y-axis direction, to inject micro-droplet on the injection target. Due to the widely application of micro-droplet injection, it plays a rather important role in the microminiaturization of the printed circuit board (PCB), color filter (CF), organic thin film transistor (OTFT), polymer lighting emission diode (PLED), bio-chip, and others.
A conventional micro-droplet injection platform is designed according to the requirements of micro-droplet injection, and includes a movable substrate stage, an injection head module, an injection head maintaining module, an image detection module, and a print control unit. However, the conventional micro-droplet injection platform often encounters the problems of jet orifices of injection head clogged and bubbles generated in the injection head, so that the problem of poor print cannot be solved effectively. Furthermore, when a maintain operation is carried out to the injection head module after finishing micro-droplet injection, it is not possible to observe the substrate image instantly or confirm the print quality instantly, causing a delay in the output time. If different micro-droplet injection processes are required, no proper manner can be provided to solve the problem occurring in the process for different substrates and micro-droplets to be injected.
U.S. Patent Publication No. U.S. Pat. No. 6,145,981 provides a method for detecting an injection effect instantly by a disable ink dot of the element to be printed when ink-injection can not reach the expectation.
U.S. Patent Publication No. U.S. Pat. No. 6,582,048 provides an injection head adjusting apparatus, which can enhance the precision of the alignment between the substrate and the injection head. It includes a position offset detection for detecting a relative position of the injection head, and an angle detection for detecting the inclined angle of the injection head, to achieve accurate alignment of the injection head and the substrate in the injection process.
U.S. Patent Publication No. U.S. Pat. No. 6,667,795 provides a micro-droplet injection apparatus with a color filter as an injection target, to achieve optimization of the injection with a space among the injection holes of the injection head.
In the former patents disclosed above, the multiplex requirement of micro-droplet injection apparatuses is not given complete consideration. In the process of injection, the precision of the alignment between the injection head and the moving stage is not sufficient, and the positioning system is not suitable. The processes for different micro-droplets and substrates cannot share one stage. The substrate yield is also seriously influenced by a poor solidification and flatness of the film plated by the micro-droplets. The injection head is not maintained thoroughly, and the operation preparation for the injection head is insufficient.